HREAD4
reg = HREAD4(sc, GPIO_PIN(pin));
reg = HREAD4(sc, GPIO_PIN(pin));
reg = HREAD4(sc, GPIO_PIN(pin));
pin, HREAD4(sc, GPIO_PIN(pin)));
reg = HREAD4(sc, GPIO_PIN(pin));
reg = HREAD4(sc, GPIO_PIN(pin));
HWRITE4((sc), (reg), HREAD4((sc), (reg)) | (bits))
HWRITE4((sc), (reg), HREAD4((sc), (reg)) & ~(bits))